Thyrotropin serum concentrations in patients with papillary thyroid microcancers

Impaired thyroid hormone sensitivity increases the risk of papillary thyroid cancer and cervical lymph node metastasis

BACKGROUND

The association of thyroid hormone sensitivity with papillary thyroid carcinoma (PTC) is unclear. This study investigated the relationship between the thyroid hormone sensitivity indices and the risk of PTC and the influence of thyroid hormone sensitivity on the aggressive clinicopathologic features of PTC.

METHODS

This retrospective study recruited 1225 PTC patients and 369 patients with benign nodules undergoing surgery in Zhongshan Hospital in 2020. The thyroid hormone sensitivity indices were thyroid feedback quantile-based index (TFQI), TSH index (TSHI) and thyrotropin thyroxine resistance index (TT4RI). We employed logistic regression models to explore the correlation between the thyroid hormone sensitivity indices and the risk of PTC and its cervical lymph node metastasis (LNM).

RESULTS

PTC patients had significantly higher levels of TSH, TFQI, TSHI and TT4RI compared to the patients with benign nodules, but thyroid hormone levels did not differ significantly between the two groups. Logistic regression analysis revealed that the higher levels of TFQI, TSHI, and TT4RI were associated with an increased risk of PTC after adjustment for multiple risk factors (TFQI: OR = 1.92, 95% CI: 1.39-2.65, P < 0.001; TSHI: OR = 2.33, 95% CI:1.67-3.26, P < 0.001; TT4RI: OR = 2.41, 95% CI:1.73-3.36, P < 0.001). In addition, patients with decreased thyroid hormone sensitivity had a higher risk of cervical LNM in multiple logistic regression analysis (TFQI: OR = 1.38, 95% CI:1.03-1.86, P = 0.03; TSHI: OR = 1.37, 95% CI:1.02-1.84, P = 0.04; TT4RI: OR = 1.41, 95% CI:1.05-1.89, P = 0.02).

CONCLUSION

Impaired sensitivity to thyroid hormone was associated with an increased risk of PTC, and it is also associated with a higher risk of cervical LNM in PTC patients.

The Relationship between Thyrotropin Serum Concentrations and Thyroid Carcinoma

Thyroid Stimulating Hormone (TSH) is a hormone secreted by the pituitary gland and plays a role in regulating the production and secretion of thyroid hormones by the thyroid gland. This precise feedback loop is essential for maintaining a harmonious balance of thyroid hormones in the body, which are vital for numerous physiological processes. Consequently, TSH serves as a significant marker in assessing thyroid function, and deviations from normal TSH levels may indicate the presence of a thyroid disorder. Thyroid cancer (TC) is the malignant tumor within the endocrine system. In recent years, numerous experts have dedicated their efforts to discovering efficacious biomarkers for TC. These biomarkers aim to improve the accurate identification of tumors with a poor prognosis, as well as facilitate active monitoring of tumors with a more favorable prognosis. The role of TSH in the thyroid gland underscores its potential influence on the occurrence and progression of TC, which has garnered attention in the scientific community. However, due to the limited scope of clinical research and the dearth of high-quality foundational studies, the precise impact of TSH on TC remains unclear. Consequently, we present a comprehensive review of this subject, aiming to offer a valuable reference for future research endeavors.

The association between serum concentration of thyroid hormones and thyroid cancer: a cohort study

The impact of serum thyroid hormone levels on thyroid cancer risk is unclear. Some studies reported that elevated thyroid-stimulating hormone (TSH) is associated with higher risk for incidence of thyroid cancer, but other studies reported no relationship. We conducted a large cohort study in 164,596 South Korean men and women who were free of thyroid cancer at baseline and underwent health examination with hormone levels of thyroid function. A parametric proportional hazard model was used to evaluate the adjusted hazard ratio (HR) and 95% CI. During 2,277,749.78 person-years of follow-up, 1280 incident thyroid cancers were identified (men = 593, women = 687). Among men, the multivariable-adjusted HR (95% CI) for thyroid cancer comparing low levels of TSH with normal levels of TSH was 2.95 (1.67-5.23), whereas the corresponding HR (95% CI) in women was 1.5 (0.88-2.55). High levels of free T4 and free T3 were also associated with incident thyroid cancer in both men and women. In clinical implication, overt hyperthyroidism is associated with thyroid cancer in both men and women. Within the euthyroid range, the highest tertile of TSH was associated with a lower risk of thyroid cancer than the lowest TSH tertile and the highest FT4 tertile was associated with a higher risk of thyroid cancer than the lowest FT4 tertile in both men and women. Our finding indicates that low levels of TSH and high levels of FT4, even within the normal range, were associated with an increased risk of incident thyroid cancer.

Association between preoperative serum TSH and tumor status in patients with papillary thyroid microcarcinoma

Thyroid-stimulating hormone (TSH) is a growth factor affecting the initiation or progression of papillary thyroid cancer (PTC). However, the relationship between preoperative serum TSH and papillary thyroid microcarcinoma (PTMC) remains controversial. To investigate the relationship between preoperative serum TSH and tumor status of PTMC, a multicentered retrospective study was performed from January 2014 to December 2016. The cohort of this study consisted of 1997 patients who underwent thyroid surgery. Serum TSH concentrations were measured and PTMC was diagnosed based on the post-operation pathological report. Results showed that the preoperative serum TSH concentration was not related to age and gender but was positively associated with tumor size. Furthermore, higher TSH level was associated with extra-thyroidal extension and lymph node metastasis (LNM). These results indicated that TSH might not be involved in the development of PTMC but may be associated with PTMC progression. Preoperative serum TSH concentration should be considered as risk predictor for tumor progression in patients with PTMC.

Diagnosis and Evaluation of Thyroid Nodules-the Clinician's Perspective

Thyroid nodules are a common clinical problem encountered in an endocrine practice. More and more thyroid nodules are now being detected on unrelated imaging studies, leading to an increased diagnosis of low-risk thyroid cancers. There is therefore a greater emphasis on risk assessment based on clinical and sonographic features to avoid morbidity secondary to unnecessary therapy. Molecular diagnostics are also being widely used to further characterize indeterminate nodules. The American Thyroid Association and American College of Radiology-Thyroid Imaging Reporting and Data System guidelines are the most commonly used in clinical practice for risk assessment.

High Urinary Iodine, Thyroid Autoantibodies, and Thyroid-Stimulating Hormone for Papillary Thyroid Cancer Risk

Thyroid nodules have become a common clinical problem, and the clinical importance of thyroid nodules lies in the determination of thyroid cancer. This study aims to evaluate the risk factors for papillary thyroid cancer (PTC) with regard to urinary iodine concentration (UIC), thyroid-stimulating hormone (TSH), thyroid peroxidase antibody (TPOAb), and thyroglobulin antibody (TGAb) in comparison to thyroid nodular goiter (NG). Among the 2041 patients, 43.8% of which showed more than adequate (UIC 200-299 μg/L) and excessive iodine (UIC ≥ 300.0 μg/L) status. Compared with adequate iodine intake, iodine deficiency (UIC < 100 μg/L) was inversely associated with multifocality (OR 0.59, P = 0.040), while more than adequate iodine intake was independently associated with an increased risk of larger tumor size (OR 1.33, P = 0.002) in female PTC patients but not in males. No significant difference in UIC was observed between patients with PTC and NG, suggesting that high iodine intake may be related with the growth of PTC, but not with its oncogenesis. Besides, positive for TPOAb and TGAb were individually associated with papillary thyroid microcarcinoma (PTMC) risk (OR 2.05 and 1.71, respectively, both P < 0.05) in female patients with tumor foci < 1 cm but not in males. Furthermore, younger age (< 46 years), TGAb positivity and small thyroid nodules in both sexes, higher TSH, TPOAb positivity, and multifocality in females could all predict PTC risk (all P < 0.05). These results might have clinical significance for managing patients with thyroid nodules and those with thyroidectomy.

Association between preoperative thyrotrophin and clinicopathological and aggressive features of papillary thyroid cancer

PURPOSE

We aimed to investigate the relation between preoperative serum thyrotrophin (TSH) and clinicopathological features in patients with papillary thyroid carcinoma (PTC) and microcarcinoma (PTMC).

METHODS

Patients who underwent thyroidectomy and diagnosed to have benign nodular disease or PTC/PTMC in our clinic were evaluated retrospectively. Patients with a previous history of thyroid surgery, patients using antithyroid medications or thyroid hormone and patients with tumors known to be unresponsive to TSH were excluded.

RESULTS

Data of 1632 patients were analyzed. Histopathological diagnosis was benign in 969 (59.4%) and malignant in 663 (40.6%) patients. Preoperative median serum TSH was significantly higher in malignant compared to benign group (1.41 IU/dL vs. 0.98 IU/dL, p < 0.001). Malignancy risk increased gradually as going from hyperthyroidism to euthyroidism and hypothyroidism (20, 40.6, and 59.1%, respectively, p < 0.05). Serum TSH was lowest in benign nodular disease, higher in PTMC and highest in PTC (p < 0.001). This was also true when patients with positive antithyroid peroxidase/antithyroglobulin and with lymphocytic thyroiditis were excluded from the analysis (p < 0.001). Serum TSH was higher in patients with bilateral tumor, capsular invasion and lymph node metastasis (LNM) compared to patients with unilateral tumor, without capsule invasion and without LNM, respectively (p = 0.036, p = 0.002, and p = 0.001, respectively). Patients with aggressive variant PTC had higher serum TSH than nonaggressive ones (p < 0.05).

CONCLUSION

Preoperative serum TSH is associated with PTMC, PTC and LNM. Serum TSH seems to be related with thyroid cancer regardless of autoimmunity. With the present study, for the first time, we showed an association between serum TSH and aggressive variants of PTC.

An overall and dose-response meta-analysis for thyrotropin and thyroid cancer risk by histological type

Thyrotropin (TSH) is thought as a risk factor for thyroid cancer. However, the effect of serum TSH might depend on histological types of thyroid cancer. We searched for related studies including serum TSH as an exposure and thyroid cancer as a result in PUBMED, EMBASE and Chinese National Knowledge Infrastructure up to April 21, 2016. This meta-analysis included 22 articles with 53,538 participants. When comparing all histological thyroid cancer, the pooled odds ratios of thyroid cancer in patients with nodules was found to increase significantly with higher serum TSH concentrations for differentiated thyroid carcinoma (1.88 vs .1.48, P = 0.0000) and papillary thyroid carcinoma (2.08 vs. 1.48, P = 0.0006). Each 1 mU/L increase of serum TSH was associated with 14% greater risk of thyroid cancer for all histological thyroid cancer, 16% for differentiated thyroid carcinoma and 22% for papillary thyroid carcinoma. In addition, high serum TSH was associated with a reduced risk for follicular thyroid carcinoma (OR = 0.73, 95% CI: 0.52, 1.02). This meta-analysis suggested high serum TSH concentration is risky for papillary thyroid carcinoma but not for follicular thyroid carcinoma.

Reactivity of thyroid papillary carcinoma cells to thyroid stimulating hormone-dominated endocrine therapy

This study investigated the effect of thyroid stimulating hormone (TSH) on the proliferation of papillary thyroid carcinoma (PTC) cells and the therapeutic effect of levothyroxine sodium (TH). PTC cells (TPC-1) were cultured using 0.1, 1.0 and 10 U/l TSH and 10⁻², 10⁻⁴ and 10⁻⁶ mol/l TH. After the appropriate concentration was screened, TPC-1 cells were further divided into control group, TSH group, TH group and TSH+TH group. The cell proliferation was detected via methyl thiazolyl tetrazolium (MTT) method, TPC-1 cell cycle was detected via flow cytometer, and the mRNA and protein expression of cyclin D1 were detected via real-time polymerase chain reaction (PCR) and enzyme-linked immunosorbent assay (ELISA). Compared with control group, TSH significantly promoted the proliferation of TPC-1 cells (P<0.05 or P<0.01), obviously promoted the transition of TPC-1 cells from G1 phase to S phase (P<0.01) and remarkably increased the mRNA and protein expression of cyclin D1 (P<0.01); but TH had a significant inhibitory effect on these results of TSH (P<0.05 or P<0.01). TSH can promote the proliferation of PTC cells, and the appropriate complement of TH can inhibit its proliferation.

Thyroid-Stimulating Hormone, Thyroid Hormones, and Risk of Papillary Thyroid Cancer: A Nested Case-Control Study

Background: The effects of thyroid-stimulating hormone (TSH) and thyroid hormones on the development of human papillary thyroid cancer (PTC) remain poorly understood.Methods: The study population consisted of 741 (341 women, 400 men) histologically confirmed PTC cases and 741 matched controls with prediagnostic serum samples stored in the Department of Defense Serum Repository. Concentrations of TSH, total T3, total T4, and free T4 were measured in serum samples. Conditional logistic regression models were used to calculate ORs and 95% confidence intervals (CI).Results: The median time between blood draw and PTC diagnosis was 1,454 days. Compared with the middle tertile of TSH levels within the normal range, serum TSH levels below the normal range were associated with an elevated risk of PTC among women (OR, 3.74; 95% CI, 1.53-9.19) but not men. TSH levels above the normal range were associated with an increased risk of PTC among men (OR, 1.96; 95% CI, 1.04-3.66) but not women. The risk of PTC decreased with increasing TSH levels within the normal range among both men and women (P_trend = 0.0005 and 0.041, respectively).Conclusions: We found a significantly increased risk of PTC associated with TSH levels below the normal range among women and with TSH levels above the normal range among men. An inverse association between PTC and TSH levels within the normal range was observed among both men and women.Impact: These results could have significant clinical implications for physicians who are managing patients with abnormal thyroid functions and those with thyroidectomy. Cancer Epidemiol Biomarkers Prev; 26(8); 1209-18. ©2017 AACR.

WOMEN IN CANCER THEMATIC REVIEW: Thyroid-stimulating hormone in thyroid cancer: does it matter?

Differentiated thyroid cancer is the most common endocrine malignancy and the incidence is increasing rapidly worldwide. Appropriate diagnosis and post-treatment monitoring of patients with thyroid tumours are critical. Fine needle aspiration cytology remains the gold standard for diagnosing thyroid cancer, and although there have been significant refinements to this technique, diagnostic surgery is often required for patients suspected to have malignancy. Serum thyroid-stimulating hormone (TSH) is higher in patients with malignant thyroid nodules than in those with benign disease, and TSH is proportionally increased in more aggressive tumours. Importantly, we have shown that the pre-operative serum TSH concentration independently predicts the presence of malignancy in subjects presenting with thyroid nodules. Establishing the use of TSH measurements in algorithms identifying high-risk thyroid nodules in routine clinical practice represents an exciting, cost-efficient and non-invasive approach to optimise thyroid cancer diagnosis. Binding of TSH to receptors on thyrocytes stimulates a number of growth promoting pathways both in normal and malignant thyroid cells, and TSH suppression with high doses of levothyroxine is routinely used after thyroidectomy to prevent cancer recurrence, especially in high-risk tumours. This review examines the relationship between serum TSH and thyroid cancer and reflects on the clinical potential of TSH measurements in diagnosis and disease monitoring.

AMERICAN ASSOCIATION OF CLINICAL ENDOCRINOLOGISTS, AMERICAN COLLEGE OF ENDOCRINOLOGY, AND ASSOCIAZIONE MEDICI ENDOCRINOLOGI MEDICAL GUIDELINES FOR CLINICAL PRACTICE FOR THE DIAGNOSIS AND MANAGEMENT OF THYROID NODULES--2016 UPDATE

Thyroid nodules are detected in up to 50 to 60% of healthy subjects. Most nodules do not cause clinically significant symptoms, and as a result, the main challenge in their management is to rule out malignancy, with ultrasonography (US) and fine-needle aspiration (FNA) biopsy serving as diagnostic cornerstones. The key issues discussed in these guidelines are as follows: (1) US-based categorization of the malignancy risk and indications for US-guided FNA (henceforth, FNA), (2) cytologic classification of FNA samples, (3) the roles of immunocytochemistry and molecular testing applied to thyroid FNA, (4) therapeutic options, and (5) follow-up strategy. Thyroid nodule management during pregnancy and in children are also addressed. On the basis of US features, thyroid nodules may be categorized into 3 groups: low-, intermediate-and high-malignancy risk. FNA should be considered for nodules ≤10 mm diameter only when suspicious US signs are present, while nodules ≤5 mm should be monitored rather than biopsied. A classification scheme of 5 categories (nondiagnostic, benign, indeterminate, suspicious for malignancy, or malignant) is recommended for the cytologic report. Indeterminate lesions are further subdivided into 2 subclasses to more accurately stratify the risk of malignancy. At present, no single cytochemical or genetic marker can definitely rule out malignancy in indeterminate nodules. Nevertheless, these tools should be considered together with clinical data, US signs, elastographic pattern, or results of other imaging techniques to improve the management of these lesions. Most thyroid nodules do not require any treatment, and levothyroxine (LT4) suppressive therapy is not recommended. Percutaneous ethanol injection (PEI) should be the first-line treatment option for relapsing, benign cystic lesions, while US-guided thermal ablation treatments may be considered for solid or mixed symptomatic benign thyroid nodules. Surgery remains the treatment of choice for malignant or suspicious nodules. The present document updates previous guidelines released in 2006 and 2010 by the American Association of Clinical Endocrinologists (AACE), American College of Endocrinology (ACE) and Associazione Medici Endocrinologi (AME).

'Incidental' and 'non-incidental' thyroid papillary microcarcinomas are two different entities

OBJECTIVE

Papillary thyroid microcarcinomas (microPTC) may be 'incidental' (Inc-microPTC), occasionally found at histology after surgery for benign disease or 'non-incidental' (Non-Inc-microPTC), diagnosed on clinical grounds. It is unclear whether these different microPTC reflect the same disease. The aim of the study was to compare Inc-microPTC and Non-Inc-microPTC for clinical and histological features as well as for serum TSH, a known factor involved in PTC development.

DESIGN

We evaluated histology and serum TSH levels of consecutive patients submitted to thyroidectomy for goiter with compressive symptoms or for cytological diagnosis suspicious/indicative of PTC.

METHODS

In total, 665 consecutive patients (259 with a single thyroid nodule, SN and 406 with a multinodular gland, MN) were included in the study. According to histology, patients were classified as: benign nodular goiter (Benign, n=291); Inc-microPTC (n=92); Non-Inc-microPTC (n=67) and PTC≥1cm (macroPTC, n=215).

RESULTS

Inc-microPTC were significantly more frequent in MN than in SN (66/406, 16.2% vs 26/259, 10.0%, P=0.02). Patients with Inc-microPTC compared with Non-Inc-microPTC were older (mean age±s.d. 53.3±13.2 years vs 44.9±14.8 years, P=0.0002), had a smaller tumor size (median 4mm vs 9mm, P<0.0001), a higher frequency of multifocality (70/92, 76.1% vs 35/67, 52.2% P=0.001) and lower levels of TSH (median 0.6mIU/L, IR: 0.4-1.0mIU/L vs value 1. mIU/L, IR: 0.6-1.4mIU/L vs P=0.0001).

CONCLUSION

Incidental and non-incidental papillary thyroid microcarcinomas appear to be two different entities.

The Effect of Thyroid-Stimulating Hormone on Tumor Size in Differentiated Thyroid Carcinoma

We evaluated the correlation between serum thyroid-stimulating hormone (TSH) levels and tumor size and other invasiveness parameters of tumor in patients with differentiated thyroid carcinoma (DTC). Several clinical studies have reported that TSH may also have a role as a regulator of the development and function of the thyroid gland. It is currently not clear whether TSH is involved in the existence of thyroid cancer or progression of thyroid cancer or both. Patients with DTC who underwent thyroid surgery between 2003 and 2008 were included this study. Preoperative serum T3, T4, and TSH levels were compared with the size and invasiveness of cancer, retrospectively. DTC was observed in 110 patients over the 5-year period. Seventy-seven (70 %) of them were euthyroid and classified as the "normal-TSH group" (NTG), and 33 (30 %) have an overt or subclinical hyperthyroidism, classified as the "low-TSH group" (LTG). The mean tumor diameter in the LTG was found to be 8.91 ± 8.03 mm; however, it was found to be 18.19 ± 16.24 mm in the NTG. There were significantly differences among the groups related to the diameter of tumor (p = 0.001). Microcarcinoma was determined in 36 patients (46.8 %) in the NTG and 23 patients (69.7 %) in the LTG (p = 0.027). Although there were no significant differences, tumor capsule invasion (33.8 vs. 18.2 %, p = 0.099) and lymphovascular invasion (16.9 vs. 6.1 %, p = 0.130) rates were higher in the NTG. These findings suggest that TSH has effects on growing and proliferation of not only normal thyroid cells but also cancer cells in DTC. This study revealed that serum TSH level can be explored as an important factor that affects the size and invasiveness of tumor in DTC.

The Usefulness of Preoperative Thyroid-Stimulating Hormone for Predicting Differentiated Thyroid Microcarcinoma

OBJECTIVE

Thyroid-stimulating hormone (TSH) is a known thyroid growth factor, but the pathogenic role of TSH in thyroid tumorigenesis is controversial. The aim of this study is to examine the relationship between preoperative TSH and differentiated thyroid microcarcinoma (DTMC).

DATA SOURCES

We searched PubMed, EMBASE, Ovid, Web of Science, and the Cochrane Library from their inception to March 2015 and performed a systematic literature review of original studies.

REVIEW METHODS

Published studies that explored the relationship between preoperative TSH and DTMC were included for the review. We calculated odds ratio referring to different TSH concentrations between DTMC and control groups and used random effects model for the meta-analysis.

RESULTS

Nine eligible studies that included 6523 patients were identified. Meta-analysis revealed that DTMC was associated with high TSH concentration (odds ratio = 1.23, 95% confidence interval = 1.03-1.46, P = .001). Metaregression analysis indicated that the disparity of control groups was the possible factor resulting in heterogeneity among the studies.

CONCLUSIONS

The risk of DTMC increases significantly in parallel with TSH concentration. These results support the hypothesis that TSH is involved in tumorgenesis of differentiated thyroid cancer.

Preoperative subclinical hyperthyroidism in patients with papillary thyroid carcinoma

Objectives

Numerous studies have reported the effects of subclinical hyperthyroidism on the cardiovascular system, osteoporosis, and metabolic syndrome. However, there are few studies examining the relationships between subclinical hyperthyroidism and thyroid cancer. The aim of this study was to investigate the relationships between preoperative subclinical hyperthyroidism and clinicopathological characteristics in patients with papillary thyroid carcinoma (PTC) in terms of thyroid-stimulating hormone (TSH) levels and TSH receptor antibody (TRAb) values.

Methods

Between January 2001 and December 2007, 462 patients were eligible for analysis in our study; we compared the clinicopathological characteristics of 39 preoperative subclinical hyperthyroidism patients with those of 423 euthyroid patients.

Results

There were no statistical differences between the 2 groups with respect to age, male to female ratio, primary tumor size, extrathyroidal extension (ETE), multifocality, lymph node metastasis, TNM and AMES stages, recurrence, and survival, despite significant difference in TSH concentrations between the 2 groups. In the evaluation for TRAb, primary tumor size was significantly larger in patients with normal TRAb than in patients with elevated TRAb. When the patients were subdivided into 4 categories according to TRAb values (<5.0%; 5.0%-10.0%; 10.1%-15.0%; >15.0%), tumor size and ETE were significantly different. However, we could not find linear relationships in the increase or decrease of TRAb values.

Conclusion

The results of our study suggest that subclinical hyperthyroidism is not independently associated with tumor aggressiveness and prognosis in PTC in spite of reduced TSH levels and increased TRAb values as compared with euthyroid patients.

Identification of a novel pax8 gene sequence variant in four members of the same family: from congenital hypothyroidism with thyroid hypoplasia to mild subclinical hypothyroidism

BACKGROUND

Congenital hypothyroidism is often secondary to thyroid dysgenesis, including thyroid agenesis, hypoplasia, ectopic thyroid tissue or cysts. Loss of function mutations in TSHR, PAX8, NKX2.1, NKX2.5 and FOXE1 genes are responsible for some forms of inherited congenital hypothyroidism, with or without hypoplastic thyroid. The aim of this study was to analyse the PAX8 gene sequence in several members of the same family in order to understand whether the variable phenotypic expression, ranging from congenital hypothyroidism with thyroid hypoplasia to mild subclinical hypothyroidism, could be associated to the genetic variant in the PAX8 gene, detected in the proband.

METHODS

We screened a hypothyroid child with thyroid hypoplasia for mutations in PAX8, TSHR, NKX2.1, NKX2.5 and FOXE1 genes. We studied the inheritance of the new variant R133W detected in the PAX8 gene in the proband's family, and we looked for the same substitution in 115 Caucasian European subjects and in 26 hypothyroid children. Functional studies were performed to assess the in vitro effect of the newly identified PAX8 gene variant.

RESULTS

A new heterozygous nucleotide substitution was detected in the PAX8 DNA-binding motif (c.397C/T, R133W) in the proband, affected by congenital hypothyroidism with thyroid hypoplasia, in his older sister, displaying a subclinical hypothyroidism associated with thyroid hypoplasia and thyroid nodules, in his father, affected by hypothyroidism with thyroid hypoplasia and thyroid nodules, and his first cousin as well, who revealed only a subclinical hypothyroidism. Functional studies of R133W-PAX8 in the HEK293 cells showed activation of the TG promoter comparable to the wild-type PAX8.

CONCLUSIONS

In vitro data do not prove that R133W-PAX8 is directly involved in the development of the thyroid phenotypes reported for family members carrying the substitution. However, it is reasonable to conceive that, in the cases of transcriptions factors, such as Pax8, which establish several interactions in different protein complexes, genetic variants could have an impact in vivo.

Preoperative TSH level and risk of thyroid cancer in patients with nodular thyroid disease: nodule size contribution

BACKGROUND

Many reports have supported the relationship between high preoperative TSH levels and risk of thyroid cancer in nodular thyroid disease (NTD).

OBJECTIVES

We investigated whether TSH levels are related to the risk of differentiated thyroid carcinoma (DTC) in patients who have undergone total thyroidectomy for NTD. The relationship between TSH and size of malignant nodule was investigated. Finally, we assessed whether TSH levels are related to DTC and presence of additional benign nodules.

PATIENTS AND METHODS

A retrospective study of 980 patients was conducted. Variables included age at diagnosis, TSH level, nodule size, gender, final histology (benign versus DTC), and type of malignancy.

RESULTS

Malignancy was present in 261 (26.6%) patients. These patients had higher median TSH levels as compared to those with no malignancy (1.61 mU/L (0.9-2.5) versus 0.9 mU/L (0.3-1.6); p-value<0.001). TSH was higher in patients with DTC in whom the largest nodule was malignant than in patients in whom the largest nodule was benign (1.80 mU/L (1.1-2.6) versus 1.38 mU/L (0.7-2.1) respectively; p-value=0.025). A significant correlation was seen between malignant nodule size and TSH level, but not between TSH levels and size of the largest benign nodule.

CONCLUSIONS

Our study supported an association between preoperative TSH levels and risk of DTC in patients with NTD. There was also a direct relationship between malignant nodule size and TSH levels. By contrast, no relationship was found between the size of benign nodules and TSH levels.

Evaluation of serum thyroid-stimulating hormone as indicator for fine-needle aspiration in patients with thyroid nodules

BACKGROUND

Recently, it has been reported that the risk of thyroid malignancy increases with increasing concentrations of serum thyroid-stimulating hormone (TSH). The purpose of this study was to determine whether or not serum TSH can be a predictor for thyroid malignancy when considering the relevant ultrasound features and clinical risk factors.

METHODS

This retrospective study included 1200 euthyroid patients with 1269 thyroid nodules who underwent ultrasound-guided fine-needle aspiration (FNA) biopsy between January and June 2009. Serum TSH, ultrasound feature, and clinical parameters were compared according to final diagnosis. Subgroup analyses were performed according to nodule size.

RESULTS

Serum TSH did not show a positive association with malignancy for all nodules and the micronodule subgroup in multivariate analysis, although they showed significant association with thyroid malignancy for the macronodule subgroup. For all nodules and the 2 subgroups, suspicious ultrasound features and younger age were significantly associated with malignancy in univariate and multivariate analyses.

CONCLUSION

Our study suggests that TSH alone is not as useful as ultrasound features in deciding whether or not to perform FNA in patients with micronodules.

Thyrotropin values in patients with micropapillary thyroid cancer versus benign nodular disease

OBJECTIVE

Studies published in the last few years suggest that increased thyroid-stimulating hormone (TSH) values are associated with increased risk of thyroid cancer and/or a more advanced stage of malignancy. The aim of this study was to explore the hypothesis that TSH may be a risk factor for thyroid cancer initiation, which was tested by comparing TSH concentrations in patients with incidental micro papillary cancer (mPTC) and controls with a negative histologic exam.

METHODS

Patients were retrospectively selected from medical records from 3 district hospitals. Patients with biochemical/histologic evidence of autoimmunity, thyroid function-interfering drugs, and autonomously functioning areas, were excluded. TSH values of 41 patients with an incidental mPTC were then compared with a sex- and age-matched group of patients who had a negative histologic exam at a 4:1 ratio (164 patients).

RESULTS

TSH was not significantly different in the mPTC group compared to the controls (1.1 ± 0.7 vs. 1.3 ± 1.0 mIU/L). After adjustment for age and gender, TSH levels were still not found to be significantly different between groups. In the mPTC group, TSH levels were not found to be a significant predictor of tumor size after adjusting for age and gender (β = 0.035, SE = 0.73, P = .844).

CONCLUSIONS

On the basis of these results, the hypothesis that TSH is involved in de novo oncogenesis of PTC is not supported.

Preoperative subclinical hypothyroidism in patients with papillary thyroid carcinoma

OBJECTIVE

To assess the effect of preoperative subclinical hypothyroidism on prognosis and on the tumour's clinicopathological features at initial diagnosis of papillary thyroid carcinoma (PTC).

MATERIALS AND METHODS

328 patients who underwent surgery for PTC between January 2001 and December 2006 were enrolled in this study. Of these, we compared 35 patients with preoperative subclinical hypothyroidism with 257 patients who were euthyroid before the operation, with respect to clinicopathological characteristics and prognosis.

RESULTS

No significant differences were observed in tumour size, extrathyroidal extension, and multifocality between subclinical hypothyroidism and euthyroid patients. Patients with subclinical hypothyroidism had a considerably lower percentage of lymph node metastasis than did euthyroid patients (8.6% vs. 21.8%, p=0.068). Although preoperative subclinical hypothyroidism decreased the risk of lymph node metastasis at 0.313 of odds ratio in the multivariate analysis, its significance was not verified (95% confidence internal, 0.089-1.092; p=0.068). Patients with preoperative subclinical hypothyroidism tended to have a better prognosis than did preoperative euthyroid patients, for both recurrence (2.9% vs. 14.0%, p=0.099) and 7-year disease-free survival (97.1% vs. 87.8%, p=0.079), during the 82-month mean follow-up period. However, even as thyroid-stimulating hormone (TSH) concentration increased, there were no consistent relationships observed between the TSH levels and the prognostic parameters.

CONCLUSION

We could find neither a consistent positive nor a negative linear relationship between TSH levels and several prognostic parameters, indicating that subclinical hypothyroidism with elevated TSH is not an independent predictor of tumour aggressiveness and poor prognosis in PTC.

Clinical implications of preoperative thyrotropin serum concentrations in patients who underwent thyroidectomy for nonfunctioning nodule(s)

Purpose

Thyroid stimulating hormone (TSH) measurement is the most sensitive screening test for thyroid dysfunction. TSH is a well-known thyroid growth factor but its pathogenic role in thyroid oncogenesis remains to be clarified. The purpose of the present study was to evaluate the relationship between clinicopathologic characteristics of nonfunctioning thyroid nodules and preoperative TSH serum concentrations.

Methods

Serum TSH concentrations can be affected by many factors. After exclusion of these confounding factors, a total of 126 patients who underwent thyroidectomy from Januray 2009 to December 2010 were included in this study. Average age was 45.4 ± 10.6 years and male:female ratio was 1:2.9. There were 11 patients with benign nodules, 34 patients with papillary thyroid microcarcinoma (PTMC) of less than 5 mm in maximal diameter, 66 patients with PTMCs of more than 5 mm but not more than 10 mm in maximal diameter, and 15 patients with papillary thyroid carcinoma (PTC) of more than 10 mm in maximal diameter.

Results

TNM stages of PTCs correlated with higher preoperative TSH serum concentrations. There were trends of higher preoperative TSH serum concentrations in patients who had extrathyroidal extension (P = 0.059) and advanced N stages (P = 0.120) but did not reach statistical significance. Patients' age, sex, and tumor volume did not seem to affect preoperative TSH serum concentrations significantly.

Conclusion

In patients who have PTCs without clinical, immunological, or ultrasonographic evidence of thyroiditis, higher preoperative TSH serum concentrations within the normal range might suggest advanced TNM stages.

External validation of a nomogram that predicts the pathological diagnosis of thyroid nodules in a Chinese population

INTRODUCTION

Nomograms are statistical predictive models that can provide the probability of a clinical event. Nomograms have better performance for the estimation of individual risks because of their increased accuracy and objectivity relative to physicians' personal experiences. Recently, a nomogram for predicting the likelihood that a thyroid nodule is malignant was introduced by Nixon. The aim of this study was to determine whether Nixon's nomogram can be validated in a Chinese population.

MATERIALS AND METHODS

All consecutive patients with thyroid nodules who underwent surgery between January and June 2012 in our hospital were enrolled to validate Nixon's nomogram. Univariate and multivariate analyses were used to identify the risk factors for thyroid carcinoma. Discrimination and calibration were employed to evaluate the performance of Nixon's model in our population.

RESULTS

A total of 348 consecutive patients with 409 thyroid nodules were enrolled. Thyroid ultrasonographic characteristics, including shape, echo texture, calcification, margins, vascularity and number (solitary vs. multiple nodules), were associated with malignance in the multivariate analysis. The discrimination of all nodules group, the group with a low risk of malignancy (predictive proportion <50%) and the group with a high risk of malignancy (predictive proportion ≥50%) using Nixon's nomogram was satisfactory, and the area under the receiver operating characteristic curve of the three groups were 0.87, 0.75 and 0.72, respectively. However, the calibration was significant (p = 0.55) only in the high-risk group.

CONCLUSION

Nixon's nomogram is a valuable predictive model for the Chinese population and has been externally validated. It has good performance for patients with a high risk of malignancy and may be more suitable for use with these patients in China.

Lack of association between high serum thyroid-stimulating hormone level and risk of papillary thyroid microcarcinomas

BACKGROUND

High serum thyroid-stimulating hormone (TSH) is associated with thyroid carcinoma in patients with thyroid nodules. However, previous studies suggests that TSH is not involved in the pathogenesis of small thyroid carcinomas. We performed this study to evaluate serum TSH as a malignancy predictor in the assessment of small thyroid nodules.

METHODS

We retrospectively analyzed 3791 patients who underwent thyroidectomy. We classified all patients into 3 to 5 groups by serum TSH or nodule size and analyzed the association of serum TSH and risk of papillary thyroid carcinoma (PTC).

RESULTS

The frequency of PTC increased as serum TSH increased. Serum TSH and older age were associated with the risk of PTC in multivariate analysis (p < .0001). In subgroup analysis, the risk of PTC increased as serum TSH increased with thyroid nodules > 1 cm (p < .05).

CONCLUSIONS

Serum TSH may not be useful for clinical risk assessment of small thyroid nodules.

Obesity is a risk factor for thyroid cancer in a large, ultrasonographically screened population

OBJECTIVE

Obesity is a well-known risk factor for many cancers, including those of the esophagus, colon, kidney, breast, and skin. However, there are few reports on the relationship between obesity and thyroid cancer. We conducted this study to determine whether obesity is a risk factor for thyroid cancer by systematically screening a selected population by ultrasonography.

DESIGN AND METHODS

We obtained data from 15,068 subjects that underwent a routine health checkup from 2007 to 2008 at the Health Screening and Promotion Center of Asan Medical Center. Thyroid ultrasonography was included in the checkup, and suspicious nodules were examined by ultrasonography-guided aspiration. Those with a history of thyroid disease or family history of thyroid cancer were excluded from this study.

RESULTS

In total, 15,068 subjects, 8491 men and 6577 women, were screened by thyroid ultrasonography. Fine-needle aspiration cytology was performed in 1427 of these patients based on the predefined criteria and thyroid cancer was diagnosed in 267 patients. The prevalence of thyroid cancer in women was associated with a high BMI (per 5 kg/m(2) increase) (odds ratios (OR)=1.63, 95% CI 1.24-2.10, P<0.001), after adjustment for age, smoking status, and TSH levels. There was no positive correlation between the prevalence of thyroid cancer in men and a high BMI (OR=1.16, 95% CI 0.85-1.57, P=0.336). There was no association between age, fasting serum insulin, or basal TSH levels and thyroid cancer in either gender.

CONCLUSIONS

Obesity was associated with a higher prevalence of thyroid cancer in women when evaluated in a routine health checkup setting. This association between risk factor and disease was unrelated to serum insulin and TSH levels. Additional studies are needed to understand the mechanism(s) behind the association of obesity with thyroid cancer risk.

Higher TSH level is a risk factor for differentiated thyroid cancer

OBJECTIVES

Higher thyroid-stimulating hormone (TSH) levels are associated with differentiated thyroid cancers (DTC). To validate this association, we compared TSH levels obtained from euthyroid patients with DTC with TSH levels from controls in the general population.

DESIGN AND PATIENTS

The case group included 1759 patients with DTC, who underwent thyroid surgery at Chonnam National University Hwasun Hospital. The control group (n = 1548), who had participated in the Thyroid Disease Prevalence Study were used as a healthy control group. The subjects were divided into four groups of similar size according to their TSH levels, with the first quartile used as a reference group.

RESULTS

The mean TSH level of the case group was significantly higher than the mean TSH level of the control group (1.95 ± 0.9 mIU/l vs 1.62 ± 0.8 mIU/l, P < 0.001), and was associated with DTC risk. Multiple logistic regression, after controlling for age, gender and the presence of a family history of thyroid cancer, showed that the odds ratios and 95% confidence intervals for the second, third and fourth quartiles of TSH levels were 1.27 (1.03-1.57), 1.55 (1.25-1.92) and 2.21 (1.78-2.74) respectively. No significant differences were observed in mean TSH levels in patients with different tumour stages and tumour sizes.

CONCLUSION

Having a high TSH level within the normal range is an independent risk factor for DTC, and may contribute to the initiation of thyroid carcinogenesis. TSH levels in patients with thyroid nodules may be used as diagnostic adjuncts for the identification of high-risk patients, who require further investigation and/or surgical intervention.

Thyroid nodule management: clinical, ultrasound and cytopathological parameters for predicting malignancy

Although fine-needle aspiration cytology is considered to be the reference method for evaluating thyroid nodules, the results are inaccurate in approximately 10-30% of cases. Several studies have attempted to predict the risk of malignancy in thyroid nodules based on age, nodularity, thyrotropin values, thyroid autoimmune disease, hot/cold nodule status, and ultrasound parameters. However, no consensus has been found, and none of these parameters has significantly affected patient management. The management of indeterminate thyroid nodules and re-biopsies of nodules with initially benign cytological results remain important and controversial topics of discussion. The Bethesda cytological system and several studies on the use of molecular markers to predict malignancy from cytological samples of thyroid nodules need further clarification. More in-depth discussions among and continuous education of the specialists involved in treating thyroid disease are necessary to improve the management of these patients. This review aims to examine the clinical, laboratory, ultrasound, and scintigraphic parameters that can be used for thyroid nodule management.

Serum TSH and risk of papillary thyroid cancer in nodular thyroid disease

CONTEXT

TSH is the main factor involved in the control of proliferation of thyrocytes. Recently, a strong relationship between serum TSH and risk of thyroid malignancy has been reported.

OBJECTIVES

The aim was to review published papers about the relationship between serum TSH and frequency of differentiated thyroid cancer.

EVIDENCE ACQUISITION

PubMed was used to identify studies focused on the relationship between TSH and differentiated thyroid cancer.

EVIDENCE SYNTHESIS

In patients with nodular thyroid disease, the risk of thyroid malignancy increases with serum TSH, and even within normal ranges, higher TSH values are associated with a higher frequency and more advanced stage of thyroid cancer. The likelihood of papillary thyroid carcinoma is reduced when TSH is lower, as in thyroid autonomy, and increased when TSH is higher, as in thyroid autoimmunity. Treatment with l-thyroxine (LT4), which reduces serum TSH, is associated with significantly lower risk of developing clinically detectable thyroid cancer.

CONCLUSIONS

TSH plays a key role in the development of clinically detectable thyroid cancer, and LT4 treatment reduces the risk of thyroid malignancy in patients with nodular thyroid disease. According to the guidelines of the main scientific societies, LT4 therapy is not currently recommended for the treatment of patients with nodular goiter. Even if the available data are not sufficient to advise LT4 treatment in all patients with nodular goiter with the aim of reducing the risk of papillary thyroid carcinoma, we propose that this indication should be reconsidered, taking into account recent evidence reported in the literature.

Usefulness of serum thyrotropin for risk prediction of differentiated thyroid cancers does not apply to microcarcinomas: results of 1,870 Chinese patients with thyroid nodules

The objectives of this study were to investigate whether preoperative serum thyrotropin (TSH) concentrations can be used for risk prediction of differentiated thyroid cancers (DTC), in particular, microcarcinomas (DTMC), which may be in an early stage of development of DTC. The cohort of this retrospective study consisted of 1,870 patients who underwent surgery on thyroid nodules at a single hospital in an iodine-sufficient region in China. Serum TSH and anti-thyroid antibodies were measured and diagnoses were based on surgical pathology reports. Of 1,870 patients, 14.4% (n=269) had DTC. Eighty-nine DTCs were DTMC. As TSH increased, the prevalence of DTC rose clearly. The odds ratio in favor of having DTC with a serum TSH 1.9-4.8 mIU/L and > 4.8 mIU/L, compared with having a serum TSH 1.0-1.9 mIU/L were 1.57 (95% CI 1.03-2.40, P=0.038) and 5.71 (95% CI 2.31-14.14, P=0.0002), respectively. A similar pattern was yielded when excluding subjects with high thyroid autoantibodies. Higher TSH was also associated with lymph node metastasis and advanced disease (stage III and IV). However, preoperative TSH was 1.17 mIU/L in patients with DTMC vs. 1.08 mIU/L in patients with benign pathology (P = 0.80). The pattern of escalating prevalence with higher TSH did not apply to DTMC. In conclusion, serum TSH is not a good risk predictor of DTMCs. Elevated TSH level may be related to advanced stage, that is, progression of thyroid cancer, but not with the development of thyroid cancer, since microcarcinomas do not have any relation with TSH level.

Serum thyrotropin as a risk factor for thyroid malignancy in euthyroid subjects with thyroid micronodule

BACKGROUND

An elevated thyroid stimulating hormone (TSH) level is a risk factor for differentiated thyroid cancer. The present study investigated whether TSH is a risk factor for thyroid microcarcinoma (TMC) in euthyroid subjects with a micronodule.

METHODS

In this cross-sectional study, 483 euthyroid subjects (77 males patients, 406 females patients) with a thyroid micronodule were enrolled and underwent ultrasound guided fine-needle aspiration biopsy. Serum TSH level was measured in every subject. The final diagnostic outcome (malignant or benign) was defined in conjunction with cytology and histology.

RESULTS

Compared with the patients below the population mean, patients above the population mean had a significantly higher malignancy rate (10.8% vs 4.8%, p = .025). Multiple logistic regression analysis revealed TSH as an independent risk factor for malignancy in euthyroid patients with a micronodule (odds ratio, 1.449; 95% confidence interval, 1.033-2.033; p = .031).

CONCLUSIONS

Measurement of TSH in subjects with a thyroid micronodule is helpful to estimate cancer risk.

Preoperative thyrotropin serum concentrations gradually increase from benign thyroid nodules to papillary thyroid microcarcinomas then to papillary thyroid cancers of larger size

We evaluated the preoperative serum thyrotropin (TSH) levels in 386 patients operated on for nodular thyroid disease (NTD). TSH levels for cases with final benign disease and differentiated thyroid carcinoma (DTC) were compared. No evidence of cancer was detected in 310 patients (80.3%), whereas malignancy was present in 76 cases (19.7%). Mean TSH concentration was 1.36 ± 1.62 mU/L in benign patients and 2.08 ± 2.1 in cases with malignant lesions (P = 0.0013). The group of malignancy was subdivided in papillary thyroid carcinoma (PTMC) versus thyroid cancer of larger size (TCLS). Mean TSH was 1.71 ± 1.52 in PTMC and 2.42 ± 2.5 in TCLS. Significant differences were found when all groups (benign, PTMC and TCLS) were compared (P < 0.001). However, pairwise comparisons between them showed that differences were only significant between benign and TCLS groups (P < 0.01). In conclusion, TSH levels were higher in patients with a final diagnosis of DTC. Moreover, it appears that there exists an increment in tumor size as a function of increment in the TSH level.

Role of ultrasound, clinical and scintigraphyc parameters to predict malignancy in thyroid nodule

Background

This study aimed to evaluate clinical, laboratory, ultrasound (US) and scintigraphyc parameters in thyroid nodule and to develop an auxiliary model for clinical application in the diagnosis of malignancy.

Methods

We assessed 143 patients who were surgically treated at a single center, 65% (93) benign vs. 35% (50) malignant lesions at final histology (1998-2008). The clinical, laboratory, scintigraphyc and US features were compared and a prediction model was designed after the multivariate analysis.

Results

There were no differences in gender, serum TSH and FT4 levels, thyroid auto-antibodies (TAb), thyroid dysfunction and scintigraphyc results (P = 0.33) between benign and malignant nodule groups. The sonographic study showed differences when the presence of suspected characteristics was found in the nodules of the malignant lesions group, such as: microcalcifications, central flow, border irregularity and hypoechogenicity. After the multivariate analysis the model obtained showed age (>39 years), border irregularity, microcalcifications and nodule size over 2 cm as predictive factors of malignancy, featuring 81.7% of accuracy.

Conclusions

This study confirmed a significant increase of risk for malignancy in patients of over 39 years and with suspicious features at US.